The use of mammography techniques for the screening and diagnosis of breast cancers has been limited by the overlapping of cancer symptoms with normal tissue structures. To overcome this problem, two methods have been developed and actively investigated recently: digital tomosynthesis mammography and cone beam breast CT. Comparison study with these three techniques will be helpful to understand...

A table-top volumetric CT system has been implemented that is able to image a 5-cm-thick volume in one circular scan with no cone-beam artifacts. The prototype inverse-geometry CT (IGCT) scanner consists of a large-area, scanned x-ray source and a detector array that is smaller in the transverse direction. The IGCT geometry provides sufficient volumetric sampling because the source and detector...

In the past few years, there has been an increasing interest of the radiation oncology community in cone-beam computed tomography (CT) scanners integrated into the gantry of medical linear accelerators. This imaging device allows to acquire CT images of the patient in treatment position. Unfortunately, like for other CT scanners, the respiratory motion of the patient during acquisition causes a...

The advanced single–slice rebinning algorithm (ASSR) is a highly accurate and efficient approximative algorithm for cone–beam spiral CT that a) yields high image quality even at large cone angles, b) makes use of available 2D backprojection algorithms/hardware and c) allows for sequential data processing. It uses virtual R–planes (reconstruction planes) that are tilted to optimally fit 180 spir...

A retromolar canal is an anatomical variation in the mandible. As it includes the neurovascular bundle, local anesthetic insufficiency can occur, and an injury of the retromolar canal during dental surgery in the mandible may result in excessive bleeding, paresthesia, and traumatic neuroma. Using imaging analysis software, we evaluated the cone-beam computed tomography (CT) images of two Korean...

chamber.The concept of CTDI is still the basis for dosimetry at modern CT scanners, although the assessment of CTDI in phantoms has been the subject of much discussion and many revisions were required since its initial definition. A fundamental revision was for example needed when helical CT was introduced and the concept of pitch had to be taken into account. With the introduction of diagnosti...

PURPOSE A new cone-beam CT scanner for image-guided radiotherapy (IGRT) can independently rotate the source and the detector along circular trajectories. Existing reconstruction algorithms are not suitable for this scanning geometry. The authors propose and evaluate a three-dimensional (3D) filtered-backprojection reconstruction for this situation. METHODS The source and the detector trajecto...

The long object problem is practically important and theoretically challenging. To solve the long object problem, spiral cone-beam CT was first proposed in 1991, and has been extensively studied since then. As a main feature of the next generation medical CT, spiral cone-beam CT has been greatly improved over the past several years, especially in terms of exact image reconstruction methods. Now...

INTRODUCTION C-arm Cone Beam CT (CBCT) is a technology that is being integrated into many of the newer angiography systems in the interventional suite. Due to its ability to provide cross sectional imaging, it has opened a myriad of opportunities for creating new clinical applications. We review the technical aspects, current reported clinical applications and potential benefits of this technol...